The Andean condor is the heaviest bird in the world, with a weight of about 16 kg. And when it comes to keeping these huge objects high, it seems the sky is very limited, according to new research.
Taking off from Earth appears to be the hardest part of the Andean Condor common in South America, and is the largest bird in the world ever by selling wings 3.2 meters away.
But as soon as these giant birds become in the air, they hardly fly with their wings, instead they slip and rise up to 99% of the time they fly, and they are able to do so mostly due to the wind currents and convective heat.
Less effort
By connecting vital recorders, or "diary logs", to eight of the young Condor birds, the researchers obtained more than 230 hours of flight time indexed. And all the while, only 1% of effort was put into flapping the wings, most of which were simply take off.
The authors wrote in a study published in the journal PNAS on the 13th of July, "We have noticed a drop in the extraordinary effort in the flight (on the level) of flap of the wings for all individuals, which is noticeable, as none of them were adult birds." .
"Even relatively inexperienced birds work for hours with the minimum need to flap," it flew for more than five hours without a single wing stroke, covering more than 170 km using airflow alone.
It is reported that lighter species such as hummingbirds flank their wings at a crazy rate, while albatross (the isotope of the condor) spends 1.2% to 14.5% of its flight slowly flapping.
Not surprising
Using continuous data from vital records, researchers identified all wing strokes from all eight condor birds in different wind and heat conditions.
Even over the mountains, where there are complex reactions of airflow, this small condor was able to travel in invisible currents of air with very little movement.
"Pilots can go up all day if the conditions are right, so the condors' performance may not seem surprising in some ways," said Swansea University biologist Emily Shepherd from Swansea University - in an interview with the BBC quoted by Science Alert.
"But the sail pilots look at the weather and decide if that is good for flying or not."
Condor birds do not have this luxury, as they usually fly to find food that is not always in easily accessible places, so you often need to ride the air currents to get there.
Ingenuity to land
And the condor birds take a lot of energy to take off, but they need ingenuity to land, so these giant birds are selective where they land.
If the condor wants to turn toward a delicate corpse on the ground, for example, it must jump from one carrier stream to another, heading towards the warm air, and sometimes, filling those gaps requires a transverse flap.
Moreover, these "hot spots" in the atmosphere are not always so, as their strength and frequency change with weather, terrain, and season, so their prediction is not always easy when heading towards Earth.
"The risk is higher when moving between the thermal currents that behave like lava flows," says Sergio Lamprocci, a biologist at the National University of Comahue in Argentina.
Even in winter, when wind conditions and thermal currents are not of the same quality, the authors found that the Andes do not want to take a path that requires them to flap.